Question and Answer in Line
Here we discover another function of line. For, directly we endeavour to construct a decorative design—that is, a design intended to adorn or to express an object or surface—we find that we must build it upon some sort of a plan, or geometric controlling network or scaffolding, so as to give it unity, rhythm, and coherence—especially so in the case of repeating designs. Even in an isolated panel or picture the necessity of this linear basis will be felt, since one cannot draw a line or define a form without demanding an answer—that is, a corresponding, re-echoing line or mass.
The curve (1. Q) is a proposition or question. It is answered or balanced by the corresponding curve (2. A), and forms the basis for a scroll design.
The five radiating lines (1) are obviously incomplete by themselves, but if we add another four, in reverse order, (2) we get a centred and symmetric motive of an anthemion character.
Wall-Paper Design
Take, however, a wall-paper. The problem is to construct a design pleasant to the eye in line, form, colour, and suggestion; which will be interesting in detail, and yet repeat upon a wall-surface without flaw, and without becoming wearisome. Moreover, one which will lend itself to being cut upon wood, if for block-printing, and which may be reproduced with a due regard to economy of means. The designer may have a square of twenty-one inches in which to make his design.